I believe people from provinces you have mentioned don't receive official salary as there are many employers there who doesn't follow the law. That's why they are moving to Calabarzon and Metro Manila. But then if you are working in a factory as per piece work in Calabarzon area or Metro Manila, you may receive below basic pay. Englishman didn't state what factory her GF is working that's why I said I don't really understand.
If they want to receive the official wages, they can apply in reputable companies in Calabarzon areas. I can assure they can receive the official salary. You are welcome to make surveys in our city which is part of Calabarzon.
http://www.cityofsantarosainformatio..._agencies.html